merge core-8-branch

12 files changed, 394 insertions, 26 deletions

diff --git a/doc/SaveResult.3 b/doc/SaveResult.3
index 51ccb23..e62d22d 100644
--- a/doc/SaveResult.3
+++ b/doc/SaveResult.3
@@ -1,7 +1,7 @@
 '\"
 '\" Copyright (c) 1997 by Sun Microsystems, Inc.
 '\" Contributions from Don Porter, NIST, 2004. (not subject to US copyright)
-'\" Copyright (c) 2018 Nathan Coulter. 
+'\" Copyright (c) 2018 Nathan Coulter.
 '\"
 '\" See the file "license.terms" for information on usage and redistribution
 '\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
diff --git a/doc/append.n b/doc/append.n
index e3bf224..99b4ece 100644
--- a/doc/append.n
+++ b/doc/append.n
@@ -20,6 +20,11 @@ Append all of the \fIvalue\fR arguments to the current value
 of variable \fIvarName\fR.  If \fIvarName\fR does not exist,
 it is given a value equal to the concatenation of all the
 \fIvalue\fR arguments.
+.VS TIP508
+If \fIvarName\fR indicate an element that does not exist of an array that has
+a default value set, the concatenation of the default value and all the
+\fIvalue\fR arguments will be stored in the array element.
+.VE TIP508
 The result of this command is the new value stored in variable
 \fIvarName\fR.
 This command provides an efficient way to build up long
@@ -44,6 +49,7 @@ puts $var
 concat(n), lappend(n)
 .SH KEYWORDS
 append, variable
-'\" Local Variables:
-'\" mode: nroff
-'\" End:
+.\" Local variables:
+.\" mode: nroff
+.\" fill-column: 78
+.\" End:
diff --git a/doc/array.n b/doc/array.n
index d6d4dff..bbfcd9f 100644
--- a/doc/array.n
+++ b/doc/array.n
@@ -5,7 +5,7 @@
 '\" See the file "license.terms" for information on usage and redistribution
 '\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 '\"
-.TH array n 8.3 Tcl "Tcl Built-In Commands"
+.TH array n 8.7 Tcl "Tcl Built-In Commands"
 .so man.macros
 .BS
 '\" Note:  do not modify the .SH NAME line immediately below!
@@ -36,6 +36,53 @@ with an empty name, since the return value from
 \fBarray nextelement\fR will not indicate whether the search
 has been completed.
 .TP
+\fBarray default \fIsubcommand arrayName args...\fR
+.VS TIP508
+Manages the default value of the array. Arrays initially have no default
+value, but this command allows you to set one; the default value will be
+returned when reading from an element of the array \farrayName\fR if the read
+would otherwise result in an error. Note that this may cause the \fBappend\fR,
+\fBdict\fR, \fBincr\fR and \fBlappend\fR commands to change their behavior in
+relation to non-existing array elements.
+.RS
+.PP
+The \fIsubcommand\fR argument controls what exact operation will be performed
+on the default value of \fIarrayName\fR. Supported \fIsubcommand\fRs are:
+.VE TIP508
+.TP
+\fBarray default exists \fIarrayName\fR
+.VS TIP508
+This returns a boolean value indicating whether a default value has been set
+for the array \fIarrayName\fR. Returns a false value if \fIarrayName\fR does
+not exist. Raises an error if \fIarrayName\fR is an existing variable that is
+not an array.
+.VE TIP508
+.TP
+\fBarray default get \fIarrayName\fR
+.VS TIP508
+This returns the current default value for the array \fIarrayName\fR.  Raises
+an error if \fIarrayName\fR is an existing variable that is not an array, or
+if \fIarrayName\fR is an array without a default value.
+.VE TIP508
+.TP
+\fBarray default set \fIarrayName value\fR
+.VS TIP508
+This sets the default value for the array \fIarrayName\fR to \fIvalue\fR.
+Returns the empty string. Raises an error if \fIarrayName\fR is an existing
+variable that is not an array, or if \fIarrayName\fR is an illegal name for an
+array. If \fIarrayName\fR does not currently exist, it is created as an empty
+array as well as having its default value set.
+.VE TIP508
+.TP
+\fBarray default unset \fIarrayName\fR
+.VS TIP508
+This removes the default value for the array \fIarrayName\fR and returns the
+empty string. Does nothing if \fIarrayName\fR does not have a default
+value. Raises an error if \fIarrayName\fR is an existing variable that is not
+an array.
+.VE TIP508
+.RE
+.TP
 \fBarray donesearch \fIarrayName searchId\fR
 This command terminates an array search and destroys all the
 state associated with that search.  \fISearchId\fR indicates
@@ -194,3 +241,7 @@ foreach color [lsort [\fBarray names\fR colorcount]] {
 list(n), string(n), variable(n), trace(n), foreach(n)
 .SH KEYWORDS
 array, element names, search
+.\" Local variables:
+.\" mode: nroff
+.\" fill-column: 78
+.\" End:
diff --git a/doc/define.n b/doc/define.n
index 6353d00..883d5fa 100644
--- a/doc/define.n
+++ b/doc/define.n
@@ -426,7 +426,7 @@ Some of the configurable definitions of a class or object are \fIslotted
 definitions\fR. This means that the configuration is implemented by a slot
 object, that is an instance of the class \fBoo::Slot\fR, which manages a list
 of values (class names, variable names, etc.) that comprises the contents of
-the slot. The class defines three operations (as methods) that may be done on
+the slot. The class defines five operations (as methods) that may be done on
 the slot:
 .TP
 \fIslot\fR \fB\-append\fR ?\fImember ...\fR?
@@ -437,6 +437,16 @@ This appends the given \fImember\fR elements to the slot definition.
 .
 This sets the slot definition to the empty list.
 .TP
+\fIslot\fR \fB\-prepend\fR ?\fImember ...\fR?
+.VS TIP516
+This prepends the given \fImember\fR elements to the slot definition.
+.VE TIP516
+.TP
+\fIslot\fR \fB\-remove\fR ?\fImember ...\fR?
+.VS TIP516
+This removes the given \fImember\fR elements from the slot definition.
+.VE TIP516
+.TP
 \fIslot\fR \fB\-set\fR ?\fImember ...\fR?
 .
 This replaces the slot definition with the given \fImember\fR elements.
@@ -454,15 +464,52 @@ and these methods which provide the implementation interface:
 .TP
 \fIslot\fR \fBGet\fR
 .
-Returns a list that is the current contents of the slot. This method must
-always be called from a stack frame created by a call to \fBoo::define\fR or
-\fBoo::objdefine\fR.
+Returns a list that is the current contents of the slot, but does not modify
+the slot. This method must always be called from a stack frame created by a
+call to \fBoo::define\fR or \fBoo::objdefine\fR. This method \fIshould not\fR
+return an error unless it is called from outside a definition context or with
+the wrong number of arguments.
+.RS
+.PP
+.VS TIP516
+The elements of the list should be fully resolved, if that is a meaningful
+concept to the slot.
+.VE TIP516
+.RE
+.TP
+\fIslot\fR \fBResolve\fR \fIslotElement\fR
+.VS TIP516
+Returns \fIslotElement\fR with a resolution operation applied to it, but does
+not modify the slot. For slots of simple strings, this is an operation that
+does nothing, whereas for slots of classes, this maps a class name to its
+fully-qualified class name.  This method must always be called from a stack
+frame created by a call to \fBoo::define\fR or \fBoo::objdefine\fR.  This
+method \fIshould not\fR return an error unless it is called from outside a
+definition context or with the wrong number of arguments; unresolvable
+arguments should be returned as is (as not all slot operations strictly
+require that values are resolvable to work).
+.RS
+.PP
+Implementations \fIshould not\fR enforce uniqueness and ordering constraints
+in this method; that is the responsibility of the \fBSet\fR method.
+.RE
+.VE TIP516
 .TP
 \fIslot\fR \fBSet \fIelementList\fR
 .
 Sets the contents of the slot to the list \fIelementList\fR and returns the
 empty string. This method must always be called from a stack frame created by
-a call to \fBoo::define\fR or \fBoo::objdefine\fR.
+a call to \fBoo::define\fR or \fBoo::objdefine\fR. This method may return an
+error if it rejects the change to the slot contents (e.g., because of invalid
+values) as well as if it is called from outside a definition context or with
+the wrong number of arguments.
+.RS
+.PP
+This method \fImay\fR reorder and filter the elements if this is necessary in
+order to satisfy the underlying constraints of the slot. (For example, slots
+of classes enforce a uniqueness constraint that places each element in the
+earliest location in the slot that it can.)
+.RE
 .PP
 The implementation of these methods is slot-dependent (and responsible for
 accessing the correct part of the class or object definition). Slots also have
@@ -470,6 +517,14 @@ an unknown method handler to tie all these pieces together, and they hide
 their \fBdestroy\fR method so that it is not invoked inadvertently. It is
 \fIrecommended\fR that any user changes to the slot mechanism be restricted to
 defining new operations whose names start with a hyphen.
+.PP
+.VS TIP516
+Most slot operations will initially \fBResolve\fR their argument list, combine
+it with the results of the \fBGet\fR method, and then \fBSet\fR the result.
+Some operations omit one or both of the first two steps; omitting the third
+would result in an idempotent read-only operation (but the standard mechanism
+for reading from slots is via \fBinfo class\fR and \fBinfo object\fR).
+.VE TIP516
 .SH EXAMPLES
 This example demonstrates how to use both forms of the \fBoo::define\fR and
 \fBoo::objdefine\fR commands (they work in the same way), as well as
diff --git a/doc/dict.n b/doc/dict.n
index cd7e94c..1829768 100644
--- a/doc/dict.n
+++ b/doc/dict.n
@@ -27,6 +27,11 @@ key maps to in the dictionary value contained in the given variable,
 writing the resulting dictionary value back to that variable.
 Non-existent keys are treated as if they map to an empty string. The
 updated dictionary value is returned.
+.VS TIP508
+If \fIdictionaryVarable\fR indicates an element that does not exist of an
+array that has a default value set, the default value and will be used as the
+value of the dictionary prior to the appending operation.
+.VE TIP508
 .TP
 \fBdict create \fR?\fIkey value ...\fR?
 .
@@ -124,6 +129,11 @@ resulting dictionary value back to that variable. Non-existent keys
 are treated as if they map to 0. It is an error to increment a value
 for an existing key if that value is not an integer. The updated
 dictionary value is returned.
+.VS TIP508
+If \fIdictionaryVarable\fR indicates an element that does not exist of an
+array that has a default value set, the default value and will be used as the
+value of the dictionary prior to the incrementing operation.
+.VE TIP508
 .TP
 \fBdict info \fIdictionaryValue\fR
 .
@@ -149,6 +159,11 @@ keys are treated as if they map to an empty list, and it is legal for
 there to be no items to append to the list. It is an error for the
 value that the key maps to to not be representable as a list. The
 updated dictionary value is returned.
+.VS TIP508
+If \fIdictionaryVarable\fR indicates an element that does not exist of an
+array that has a default value set, the default value and will be used as the
+value of the dictionary prior to the list-appending operation.
+.VE TIP508
 .TP
 \fBdict map \fR{\fIkeyVariable valueVariable\fR} \fIdictionaryValue body\fR
 .
@@ -206,6 +221,11 @@ value and places an updated dictionary value in that variable
 containing a mapping from the given key to the given value. When
 multiple keys are present, this operation creates or updates a chain
 of nested dictionaries. The updated dictionary value is returned.
+.VS TIP508
+If \fIdictionaryVarable\fR indicates an element that does not exist of an
+array that has a default value set, the default value and will be used as the
+value of the dictionary prior to the value insert/update operation.
+.VE TIP508
 .TP
 \fBdict size \fIdictionaryValue\fR
 .
@@ -221,6 +241,11 @@ through nested dictionaries to the mapping to remove. At least one key
 must be specified, but the last key on the key-path need not exist.
 All other components on the path must exist. The updated dictionary
 value is returned.
+.VS TIP508
+If \fIdictionaryVarable\fR indicates an element that does not exist of an
+array that has a default value set, the default value and will be used as the
+value of the dictionary prior to the value remove operation.
+.VE TIP508
 .TP
 \fBdict update \fIdictionaryVariable key varName \fR?\fIkey varName ...\fR? \fIbody\fR
 .
@@ -236,6 +261,11 @@ are silently discarded), even if the result of \fIbody\fR is an error
 or some other kind of exceptional exit. The result of \fBdict
 update\fR is (unless some kind of error occurs) the result of the
 evaluation of \fIbody\fR.
+.VS TIP508
+If \fIdictionaryVarable\fR indicates an element that does not exist of an
+array that has a default value set, the default value and will be used as the
+value of the dictionary prior to the update operation.
+.VE TIP508
 .RS
 .PP
 Each \fIvarName\fR is mapped in the scope enclosing the \fBdict update\fR;
@@ -270,6 +300,11 @@ dictionary be discarded, and this also happens if the contents of
 dictionaries no longer exists. The result of \fBdict with\fR is
 (unless some kind of error occurs) the result of the evaluation of
 \fIbody\fR.
+.VS TIP508
+If \fIdictionaryVarable\fR indicates an element that does not exist of an
+array that has a default value set, the default value and will be used as the
+value of the dictionary prior to the updating operation.
+.VE TIP508
 .RS
 .PP
 The variables are mapped in the scope enclosing the \fBdict with\fR;
diff --git a/doc/exec.n b/doc/exec.n
index d78c34a..99dfdc5 100644
--- a/doc/exec.n
+++ b/doc/exec.n
@@ -224,10 +224,10 @@ Although it is the common escape algorithm, but, in fact, the way how the
 executable parses the command-line (resp. splits it into single arguments)
 is decisive.
 .PP
-Unfortunately, there is currently no way to supply newline character within 
-an argument to the batch files (\fB.cmd\fR or \fB.bat\fR) or to the command 
+Unfortunately, there is currently no way to supply newline character within
+an argument to the batch files (\fB.cmd\fR or \fB.bat\fR) or to the command
 processor (\fBcmd.exe /c\fR), because this causes truncation of command-line
-(also the argument chain) on the first newline character. 
+(also the argument chain) on the first newline character.
 But it works properly with an executable (using CommandLineToArgv, etc).
 .PP
 The Tk console text widget does not provide real standard IO capabilities.
diff --git a/doc/http.n b/doc/http.n
index 40ced23..7e633b3 100644
--- a/doc/http.n
+++ b/doc/http.n
@@ -6,14 +6,14 @@
 '\" See the file "license.terms" for information on usage and redistribution
 '\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 '\"
-.TH "http" n 2.7 http "Tcl Bundled Packages"
+.TH "http" n 2.9 http "Tcl Bundled Packages"
 .so man.macros
 .BS
 '\" Note:  do not modify the .SH NAME line immediately below!
 .SH NAME
 http \- Client-side implementation of the HTTP/1.1 protocol
 .SH SYNOPSIS
-\fBpackage require http ?2.7?\fR
+\fBpackage require http ?2.8?\fR
 .\" See Also -useragent option documentation in body!
 .sp
 \fB::http::config ?\fI\-option value\fR ...?
@@ -22,6 +22,8 @@ http \- Client-side implementation of the HTTP/1.1 protocol
 .sp
 \fB::http::formatQuery\fR \fIkey value\fR ?\fIkey value\fR ...?
 .sp
+\fB::http::quoteString\fR \fIvalue\fR
+.sp
 \fB::http::reset\fR \fItoken\fR ?\fIwhy\fR?
 .sp
 \fB::http::wait \fItoken\fR
@@ -44,12 +46,14 @@ http \- Client-side implementation of the HTTP/1.1 protocol
 .sp
 \fB::http::register \fIproto port command\fR
 .sp
+\fB::http::registerError \fIport\fR ?\fImessage\fR?
+.sp
 \fB::http::unregister \fIproto\fR
 .BE
 .SH DESCRIPTION
 .PP
 The \fBhttp\fR package provides the client side of the HTTP/1.1
-protocol, as defined in RFC 2616.
+protocol, as defined in RFC 7230 to RFC 7235, which supersede RFC 2616.
 The package implements the GET, POST, and HEAD operations
 of HTTP/1.1.  It allows configuration of a proxy host to get through
 firewalls.  The package is compatible with the \fBSafesock\fR security
@@ -95,6 +99,19 @@ comma-separated list of mime type patterns that you are
 willing to receive.  For example,
 .QW "image/gif, image/jpeg, text/*" .
 .TP
+\fB\-pipeline\fR \fIboolean\fR
+.
+Specifies whether HTTP/1.1 transactions on a persistent socket will be
+pipelined.  See the \fBPERSISTENT SOCKETS\fR section for details. The default
+is 1.
+.TP
+\fB\-postfresh\fR \fIboolean\fR
+.
+Specifies whether requests that use the \fBPOST\fR method will always use a
+fresh socket, overriding the \fB-keepalive\fR option of
+command \fBhttp::geturl\fR.  See the \fBPERSISTENT SOCKETS\fR section for details.
+The default is 0.
+.TP
 \fB\-proxyhost\fR \fIhostname\fR
 .
 The name of the proxy host, if any.  If this value is the
@@ -116,20 +133,47 @@ an empty list.  The default filter returns the values of the
 \fB\-proxyhost\fR and \fB\-proxyport\fR settings if they are
 non-empty.
 .TP
+\fB\-repost\fR \fIboolean\fR
+.
+Specifies what to do if a POST request over a persistent connection fails
+because the server has half-closed the connection.  If boolean \fBtrue\fR, the
+request
+will be automatically retried; if boolean \fBfalse\fR it will not, and the
+application
+that uses \fBhttp::geturl\fR is expected to seek user confirmation before
+retrying the POST.  The value \fBtrue\fR should be used only under certain
+conditions. See the \fBPERSISTENT SOCKETS\fR section for details. The
+default is 0.
+.TP
 \fB\-urlencoding\fR \fIencoding\fR
 .
 The \fIencoding\fR used for creating the x-url-encoded URLs with
-\fB::http::formatQuery\fR.  The default is \fButf-8\fR, as specified by RFC
+\fB::http::formatQuery\fR and \fB::http::quoteString\fR.
+The default is \fButf-8\fR, as specified by RFC
 2718.  Prior to http 2.5 this was unspecified, and that behavior can be
 returned by specifying the empty string (\fB{}\fR), although
 \fIiso8859-1\fR is recommended to restore similar behavior but without the
-\fB::http::formatQuery\fR throwing an error processing non-latin-1
-characters.
+\fB::http::formatQuery\fR or \fB::http::quoteString\fR
+throwing an error processing non-latin-1 characters.
 .TP
 \fB\-useragent\fR \fIstring\fR
 .
-The value of the User-Agent header in the HTTP request.  The default is
-.QW "\fBTcl http client package 2.7\fR" .
+The value of the User-Agent header in the HTTP request.  In an unsafe
+interpreter, the default value depends upon the operating system, and
+the version numbers of \fBhttp\fR and \fBTcl\fR, and is (for example)
+.QW "\fBMozilla/5.0 (Windows; U; Windows NT 10.0) http/2.8.12 Tcl/8.6.8\fR" .
+A safe interpreter cannot determine its operating system, and so the default
+in a safe interpreter is to use a Windows 10 value with the current version
+numbers of \fBhttp\fR and \fBTcl\fR.
+.TP
+\fB\-zip\fR \fIboolean\fR
+.
+If the value is boolean \fBtrue\fR, then by default requests will send a header
+.QW "\fBAccept-Encoding: gzip,deflate,compress\fR" .
+If the value is boolean \fBfalse\fR, then by default this header will not be sent.
+In either case the default can be overridden for an individual request by
+supplying a custom \fBAccept-Encoding\fR header in the \fB-headers\fR option
+of \fBhttp::geturl\fR. The default is 1.
 .RE
 .TP
 \fB::http::geturl\fR \fIurl\fR ?\fIoptions\fR?
@@ -227,7 +271,7 @@ Pragma: no-cache
 .TP
 \fB\-keepalive\fR \fIboolean\fR
 .
-If true, attempt to keep the connection open for servicing
+If boolean \fBtrue\fR, attempt to keep the connection open for servicing
 multiple requests.  Default is 0.
 .TP
 \fB\-method\fR \fItype\fR
@@ -334,6 +378,11 @@ encodes the keys and values, and generates one string that has the
 proper & and = separators.  The result is suitable for the
 \fB\-query\fR value passed to \fB::http::geturl\fR.
 .TP
+\fB::http::quoteString\fR \fIvalue\fR
+.
+This procedure does x-url-encoding of string.  It takes a single argument and
+encodes it.
+.TP
 \fB::http::reset\fR \fItoken\fR ?\fIwhy\fR?
 .
 This command resets the HTTP transaction identified by \fItoken\fR, if any.
@@ -415,6 +464,17 @@ set token [::http::geturl https://my.secure.site/]
 .CE
 .RE
 .TP
+\fB::http::registerError\fR \fIport\fR ?\fImessage\fR?
+.
+This procedure allows a registered protocol handler to deliver an error
+message for use by \fBhttp\fR.  Calling this command does not raise an
+error. The command is useful when a registered protocol detects an problem
+(for example, an invalid TLS certificate) that will cause an error to
+propagate to \fBhttp\fR.  The command allows \fBhttp\fR to provide a
+precise error message rather than a general one.  The command returns the
+value provided by the last call with argument \fImessage\fR, or the empty
+string if no such call has been made.
+.TP
 \fB::http::unregister\fR \fIproto\fR
 .
 This procedure unregisters a protocol handler that was previously
@@ -504,6 +564,14 @@ The following elements of
 the array are supported:
 .RS
 .TP
+\fBbinary\fR
+.
+This is boolean \fBtrue\fR if (after decoding any compression specified
+by the
+.QW "Content-Encoding"
+response header) the HTTP response is binary.  It is boolean \fBfalse\fR
+if the HTTP response is text.
+.TP
 \fBbody\fR
 .
 The contents of the URL.  This will be empty if the \fB\-channel\fR
@@ -602,6 +670,106 @@ A copy of the \fBContent-Type\fR meta-data value.
 .
 The requested URL.
 .RE
+.SH "PERSISTENT CONNECTIONS"
+.PP
+.SS "BASICS"
+.PP
+See RFC 7230 Sec 6, which supersedes RFC 2616 Sec 8.1.
+.PP
+A persistent connection allows multiple HTTP/1.1 transactions to be
+carried over the same TCP connection.  Pipelining allows a
+client to make multiple requests over a persistent connection without
+waiting for each response.  The server sends responses in the same order
+that the requests were received.
+.PP
+If a POST request fails to complete, typically user confirmation is
+needed before sending the request again.  The user may wish to verify
+whether the server was modified by the failed POST request, before
+sending the same request again.
+.PP
+A HTTP request will use a persistent socket if the call to
+\fBhttp::geturl\fR has the option \fB-keepalive true\fR. It will use
+pipelining where permitted if the \fBhttp::config\fR option
+\fB-pipeline\fR is boolean \fBtrue\fR (its default value).
+.PP
+The http package maintains no more than one persistent connection to each
+server (i.e. each value of
+.QW "domain:port" ).
+If \fBhttp::geturl\fR is called to make a request over a persistent
+connection while the connection is busy with another request, the new
+request will be held in a queue until the connection is free.
+.PP
+The http package does not support HTTP/1.0 persistent connections
+controlled by the \fBKeep-Alive\fR header.
+.SS "SPECIAL CASES"
+.PP
+This subsection discusses issues related to closure of the
+persistent connection by the server, automatic retry of failed requests,
+the special treatment necessary for POST requests, and the options for
+dealing with these cases.
+.PP
+In accordance with RFC 7230, \fBhttp::geturl\fR does not pipeline
+requests that use the POST method.  If a POST uses a persistent
+connection and is not the first request on that connection,
+\fBhttp::geturl\fR waits until it has received the response for the previous
+request; or (if \fBhttp::config\fR option \fB-postfresh\fR is boolean \fBtrue\fR) it
+uses a new connection for each POST.
+.PP
+If the server is processing a number of pipelined requests, and sends a
+response header
+.QW "\fBConnection: close\fR"
+with one of the responses (other than the last), then subsequent responses
+are unfulfilled. \fBhttp::geturl\fR will send the unfulfilled requests again
+over a new connection.
+.PP
+A difficulty arises when a HTTP client sends a request over a persistent
+connection that has been idle for a while.  The HTTP server may
+half-close an apparently idle connection while the client is sending a
+request, but before the request arrives at the server: in this case (an
+.QW "asynchronous close event" )
+the request will fail.  The difficulty arises because the client cannot
+be certain whether the POST modified the state of the server.  For HEAD or
+GET requests, \fBhttp::geturl\fR opens another connection and retransmits
+the failed request. However, if the request was a POST, RFC 7230 forbids
+automatic retry by default, suggesting either user confirmation, or
+confirmation by user-agent software that has semantic understanding of
+the application.  The \fBhttp::config\fR option \fB-repost\fR allows for
+either possibility.
+.PP
+Asynchronous close events can occur only in a short interval of time.  The
+\fBhttp\fR package monitors each persistent connection for closure by the
+server.  Upon detection, the connection is also closed at the client end,
+and subsequent requests will use a fresh connection.
+.PP
+If the \fBhttp::geturl\fR command is called with option \fB-keepalive true\fR,
+then it will both try to use an existing persistent connection
+(if one is available), and it will send the server a
+.QW "\fBConnection: keep-alive\fR"
+request header asking to keep the connection open for future requests.
+.PP
+The \fBhttp::config\fR options \fB-pipeline\fR, \fB-postfresh\fR, and
+\fB-repost\fR relate to persistent connections.
+.PP
+Option \fB-pipeline\fR, if boolean \fBtrue\fR, will pipeline GET and HEAD requests
+made
+over a persistent connection.  POST requests will not be pipelined - if the
+POST is not the first transaction on the connection, its request will not
+be sent until the previous response has finished.  GET and HEAD requests
+made after a POST will not be sent until the POST response has been
+delivered, and will not be sent if the POST fails.
+.PP
+Option \fB-postfresh\fR, if boolean \fBtrue\fR, will override the \fBhttp::geturl\fR option
+\fB-keepalive\fR, and always open a fresh connection for a POST request.
+.PP
+Option \fB-repost\fR, if \fBtrue\fR, permits automatic retry of a POST request
+that fails because it uses a persistent connection that the server has
+half-closed (an
+.QW "asynchronous close event" ).
+Subsequent GET and HEAD requests in a failed pipeline will also be retried.
+\fIThe -repost option should be used only if the application understands
+that the retry is appropriate\fR - specifically, the application must know
+that if the failed POST successfully modified the state of the server, a repeat POST
+would have no adverse effect.
 .SH EXAMPLE
 .PP
 This example creates a procedure to copy a URL to a file while printing a
diff --git a/doc/incr.n b/doc/incr.n
index b4be95c..f491903 100644
--- a/doc/incr.n
+++ b/doc/incr.n
@@ -27,6 +27,11 @@ and also returned as result.
 Starting with the Tcl 8.5 release, the variable \fIvarName\fR passed
 to \fBincr\fR may be unset, and in that case, it will be set to
 the value \fIincrement\fR or to the default increment value of \fB1\fR.
+.VS TIP508
+If \fIvarName\fR indicate an element that does not exist of an array that has
+a default value set, the sum of the default value and the \fIincrement\fR (or
+1) will be stored in the array element.
+.VE TIP508
 .SH EXAMPLES
 .PP
 Add one to the contents of the variable \fIx\fR:
@@ -59,3 +64,7 @@ an error if it is not):
 expr(n), set(n)
 .SH KEYWORDS
 add, increment, variable, value
+.\" Local variables:
+.\" mode: nroff
+.\" fill-column: 78
+.\" End:
diff --git a/doc/lappend.n b/doc/lappend.n
index 80d075a..66bea5f 100644
--- a/doc/lappend.n
+++ b/doc/lappend.n
@@ -22,6 +22,12 @@ and appends each of the \fIvalue\fR arguments to that list as a separate
 element, with spaces between elements.
 If \fIvarName\fR does not exist, it is created as a list with elements
 given by the \fIvalue\fR arguments.
+.VS TIP508
+If \fIvarName\fR indicate an element that does not exist of an array that has
+a default value set, list that is comprised of the default value with all the
+\fIvalue\fR arguments appended as elements will be stored in the array
+element.
+.VE TIP508
 \fBLappend\fR is similar to \fBappend\fR except that the \fIvalue\fRs
 are appended as list elements rather than raw text.
 This command provides a relatively efficient way to build up
@@ -47,3 +53,7 @@ list(n), lindex(n), linsert(n), llength(n), lset(n),
 lsort(n), lrange(n)
 .SH KEYWORDS
 append, element, list, variable
+.\" Local variables:
+.\" mode: nroff
+.\" fill-column: 78
+.\" End:
diff --git a/doc/lreplace.n b/doc/lreplace.n
index d19f0cd..35a9130 100644
--- a/doc/lreplace.n
+++ b/doc/lreplace.n
@@ -30,13 +30,26 @@ list, and \fBend\fR refers to the last element of the list.
 If \fIlist\fR is empty, then \fIfirst\fR and \fIlast\fR are ignored.
 .PP
 If \fIfirst\fR is less than zero, it is considered to refer to before the
-first element of the list.  For non-empty lists, the element indicated
-by \fIfirst\fR must exist or \fIfirst\fR must indicate before the
+first element of the list.
+.VS TIP505
+If \fIfirst\fR indicates a position greater than the index of the last element
+of the list, it is treated as if it is an index one greater than the last
+element. This allows this command to append elements to the list.
+.VE TIP505
+For non-empty lists, the element indicated
+by \fIfirst\fR must exist, or \fIfirst\fR must indicate before the
 start of the list.
 .PP
 If \fIlast\fR is less than \fIfirst\fR, then any specified elements
 will be inserted into the list before the point specified by \fIfirst\fR
 with no elements being deleted.
+.VS TIP505
+If \fIlast\fR is greater than the index of the last item of the list, it is
+treated as if it is an index one greater than the last element. This means
+that if it is also greater than than \fIfirst\fR, all elements from
+\fIfirst\fR to the end of the list will be replaced, and otherwise the
+elements will be appended.
+.VE TIP505
 .PP
 The \fIelement\fR arguments specify zero or more new arguments to
 be added to the list in place of those that were deleted.
@@ -78,9 +91,26 @@ proc lremove {listVariable value} {
     set var [\fBlreplace\fR $var $idx $idx]
 }
 .CE
+.PP
+.VS TIP505
+Adding elements to the end of the list; note that \fBend+2\fR will initially
+be treated as if it is \fB6\fR here, but both that and \fB12345\fR are greater
+than the index of the final item so they behave identically:
+.PP
+.CS
+% set var {a b c d e}
+a b c d e
+% set var [\fBlreplace\fR $var 12345 end+2 f g h i]
+a b c d e f g h i
+.CE
+.VE TIP505
 .SH "SEE ALSO"
 list(n), lappend(n), lindex(n), linsert(n), llength(n), lsearch(n),
 lset(n), lrange(n), lsort(n),
 string(n)
 .SH KEYWORDS
 element, list, replace
+.\" Local variables:
+.\" mode: nroff
+.\" fill-column: 78
+.\" End:
diff --git a/doc/uplevel.n b/doc/uplevel.n
index 4decc6d..cda1652 100644
--- a/doc/uplevel.n
+++ b/doc/uplevel.n
@@ -24,9 +24,9 @@ the result of that evaluation.
 If \fIlevel\fR is an integer then
 it gives a distance (up the procedure calling stack) to move before
 executing the command.  If \fIlevel\fR consists of \fB#\fR followed by
-a number then the number gives an absolute level number.  If \fIlevel\fR
+a integer then the level gives an absolute level.  If \fIlevel\fR
 is omitted then it defaults to \fB1\fR.  \fILevel\fR cannot be
-defaulted if the first \fIcommand\fR argument starts with a digit or \fB#\fR.
+defaulted if the first \fIcommand\fR argument is an integer or starts with \fB#\fR.
 .PP
 For example, suppose that procedure \fBa\fR was invoked
 from top-level, and that it called \fBb\fR, and that \fBb\fR called \fBc\fR.
diff --git a/doc/zipfs.3 b/doc/zipfs.3
index 7514525..ce5d5eb 100644
--- a/doc/zipfs.3
+++ b/doc/zipfs.3
@@ -47,6 +47,10 @@ If a file named \fBmain.tcl\fR is located in that file system, it is treated
 as the startup script for the process. If the file \fIZIPROOT\fR\fB/app/tcl_library/init.tcl\fR
 is present, \fBtcl_library\fR is set to  \fIZIPROOT\fR\fB/app/tcl_library.
 .PP
+On Windows, \fBTclZipfs_AppHook()\fR has a slightly different signature, it uses
+WCHAR in stead of char. As a result, it only works if your application is compiled
+using -DUNICODE.
+.PP
 If the \fBtcl_library\fR was not found in the application, the system will then search for it
 as either a VFS attached to the application dynamic library, or as a zip archive named
 libtcl_\fIMAJOR\fR_\fIMINOR\fR_\fIpatchLevel\fR.zip either in the present working directory